What is proper workaround for @BeforeAll in Kotlin

Question

Currently the JUnit 5 API only allows @BeforeAll on a method that is static.

So if I do something like this, it will not compile:

@BeforeAll
  fun setup() {
    MockitoAnnotations.initMocks(this)
    mvc = MockMvcBuilders.standaloneSetup(controller).build()
}

In order to have a static method in Kotlin, I have to use companion object like this:

companion object {
    @JvmStatic
    @BeforeAll
    fun setup() {
      MockitoAnnotations.initMocks(this)
      mvc = MockMvcBuilders.standaloneSetup(smsController).build()
    }
}

This will compile, but I don't have access to variables from the parent class. So what would be the idiomatic way to invoke JUnit 5 @BeforeAll with Kotlin?

Answer 1

JUnit 5 has @TestInstance(PER_CLASS) annotation that can be used for this purpose. One of the features that it enables is non-static BeforeAll and AfterAll methods:

@TestInstance(PER_CLASS)
class BeforeAllTests {

    lateinit var isInit = false

    @BeforeAll
    fun setup() {
        isInit = true
    }

   @TestFactory
   fun beforeAll() = listOf(
       should("initialize isInit in BeforeAll") {
           assertTrue(isInit)
       }
   )
}

fun should(name: String, test: () -> Unit) = DynamicTest.dynamicTest("should $name", test)